Dynamic compensation control for elevator systems

Abstract

Methods and systems of controlling elevators including detecting a landing stop for an elevator car, measuring load information associated with the stop, controlling stopping of the elevator at the landing using a machine based on at least one of the detected landing and the measured load information and performing dynamic compensation control of a motion state of the elevator with a computing system and the elevator machine. The dynamic compensation control includes receiving motion state information related to at least one motion state of the elevator car at the computing system, receiving the landing and load information at the computing system, applying a filter to the received information and generating a first control signal, and producing a control output from the first control signal to control the elevator machine to minimize oscillations, vibrations, excessive position deflections, and/or bounce of the elevator car at the detected landing.

What is claimed is: 
     
       1. A method of controlling an elevator system, the method comprising:
 detecting a landing of a stop for an elevator car; 
 determining load information of a load carried by the elevator car and associated with a stopping of the elevator car at the detected landing; 
 controlling the stopping of the elevator car at the landing using an elevator machine based on the detected landing and the load information; and 
 performing dynamic compensation control of a motion state of the elevator car relative to the landing with a computing system and the elevator machine based on the detected landing and load information, 
 wherein the dynamic compensation control comprises: 
 receiving motion state information related to at least one motion state of the elevator car at the computing system; 
 receiving landing information associated with the detected landing and the load information at the computing system; 
 applying a Notch filter to the received information and generating a first control signal, wherein the Notch filter is adjusted based on at least one of hoistway dynamics and performance requirements, and wherein the Notch filter is configured to predict a bounce mode frequency as a function of the landing of the stop and the load information; and 
 producing a control output from the first control signal to control the elevator machine to minimize oscillations, vibrations, excessive position deflections, and/or bounce of the elevator car at the detected landing, 
 wherein the motion state information comprises (i) an absolute position of the elevator car within an elevator shaft and (ii) at least one of a car velocity and a car acceleration, 
 wherein the absolute position of the elevator car is determined using a plurality of inductive sensors, the inductive sensors include a tag assembly arranged within the elevator shaft proximate the detected landing and a sensor assembly arranged on the elevator car, wherein the sensor assembly is configured to inductively interact with the tag assembly to determine an absolute position of the elevator car within the elevator shaft. 
 
     
     
       2. The method of  claim 1 , wherein the control output is a current to generate a motor torque at the elevator machine. 
     
     
       3. The method of  claim 1 , further comprising applying a limiter to the first control signal to produce a second control signal. 
     
     
       4. The method of  claim 3 , further comprising:
 receiving the second control signal at a machine velocity controller; 
 receiving a motor velocity signal related to a motor velocity of the elevator machine; and 
 generating a third control signal. 
 
     
     
       5. The method of  claim 4 , further comprising receiving the third control signal at a machine torque controller and outputting the control output from the machine torque controller to control a torque of the elevator machine. 
     
     
       6. The method of  claim 1 , wherein the load information comprises at least one of (i) a current load within the elevator car, (ii) an estimated change in load due to load exiting the elevator car onto the landing, or (iii) an estimated change in load due to load entering the elevator car from the landing. 
     
     
       7. The method of  claim 1 , further comprising determining the dynamic compensation control is not required based on at least one of the load information and the detected landing. 
     
     
       8. An elevator control system comprising:
 an elevator machine operably connected to an elevator car located within an elevator shaft; 
 at least one motion state sensor arranged to detect a motion state of the elevator car within the elevator shaft; 
 at least one load sensor arranged to detect a load of the elevator car; and 
 a computing system in communication with the at least one motion state sensor and the at least one load sensor, the computing system configured to perform dynamic compensation control of the elevator car based on a detected landing where the elevator car will be stopping and a measured load; 
 wherein the dynamic compensation control comprises: 
 receiving motion state information related to the elevator car at the computing system from the at least one motion state sensor to generate a motion state signal; 
 receiving one or more load information signals at the computing system from the at least one load sensor; 
 applying a Notch filter to the motion state signal and the one or more load information signals and generating a first control signal, wherein the Notch filter is adjusted based on at least one of hoistway dynamics and performance requirements, and wherein the Notch filter is configured to predict a bounce mode frequency as a function of the landing of the stop and the one or more load information signals; and 
 producing a control output from the first control signal to control the elevator machine to minimize oscillations, vibrations, excessive position deflections, and/or bounce of the elevator car at the detected landing where the elevator car is making a stop, 
 wherein the motion state information comprises (i) an absolute position of the elevator car within the elevator shaft and (ii) at least one of a car velocity and a car acceleration, and 
 wherein the elevator control system comprises a plurality of inductive sensors configured to determine the absolute position of the elevator car within the elevator shaft, the inductive sensors include a tag assembly arranged within the elevator shaft proximate the detected landing and a sensor assembly arranged on the elevator car, wherein the sensor assembly is configured to inductively interact with the tag assembly to determine an absolute position of the elevator car within the elevator shaft. 
 
     
     
       9. The system of  claim 8 , wherein the control output is a current to generate a motor torque at the elevator machine. 
     
     
       10. The system of  claim 8 , further comprising applying a limiter to the first control signal to produce a second control signal. 
     
     
       11. The system of  claim 10 , further comprising:
 receiving the second control signal at a machine velocity controller; 
 receiving a motor velocity signal related to a motor velocity of the elevator machine; and 
 generating a third control signal. 
 
     
     
       12. The system of  claim 11 , further comprising receiving the third control signal at a machine torque controller and outputting the control output from the machine torque controller to control a torque of the elevator machine. 
     
     
       13. The system of  claim 8 , wherein the one or more load information signals comprises at least one of (i) a current load within the elevator car, (ii) an estimated change in load due to load exiting the elevator car onto the detected landing, or (iii) an estimated change in load due to load entering the elevator car from the detected landing. 
     
     
       14. The system of  claim 8 , further comprising determining the dynamic compensation control is not required based on at least one of the one or more load information signals and the detected landing. 
     
     
       15. The system of  claim 8 , wherein the Notch filter is adjusted based on at least one of (i) hoistway dynamics as directly or implied by car motion state sensing, (ii) load weighing sensors, (iii) performance requirements, or (iv) instantaneous detection of car load. 
     
     
       16. The system of  claim 8 , wherein the at least one motion state sensor comprises a plurality of sensing elements located on the elevator car and a corresponding set of tag elements located at each landing of a plurality of landings along the elevator shaft. 
     
     
       17. The system of  claim 16 , wherein the plurality of sensing elements and corresponding tag elements at each landing form overlapping detection regions.